A search engine, such as Yahoo!®, is an example of an entity that takes in and handles user queries. A query may be, for example, a keyword search in a web browser at the home page of Yahoo!®. Occasionally, a particular query is that of multiple users and may exhibit a sudden change in volume and rate.
Analyzing a query stream to identify queries that exhibit a sudden change in volume and rate is a valuable task. Such analyses of query streams can be used to influence various components of the search engine in one of several ways. Unfortunately, conventional methods of analyzing query streams do not comprehensively analyze query logs in real-time to identify queries that exhibit an unusual change in volume and/or rate.